Things that could maybe use some improvements.
My eyes. I don't know what it is. But some games have this effect on my eyes. Where after I play for a while I have a lot of trouble with my vision and to an extent my coordination after I stop. Don't know if it's the brightness, all the shiny glossy maps and defenders, or something to do with the motion and view your eyes follow while playing the game. Don't think this happened much to me in DD1 or DD2, so something has changed there. To gain some perspective, it also happens a lot in games like NBA Playgrounds and Alienation, so probably just an edge case for your userbase. My eyes see a bit different than most people, and not in a good way, so maybe just me.
Repairing anything in a stack is a pain, there should be a keybind to go to the next item or it should default where the repair cursor goes based on what defense has the most health missing. Because otherwise during waves you are stuck repairing the same electric aura 11 times in a row, since they lose some health with no enemies around and need to be repaired immediately. I also lose track of my mouse cursor and have to shake it around the screen for a few seconds before I can find it during the transition to the view from above for repairing.
Shift should toggle item compare, shouldn't have to hold it.
There are only 5 stats on Offense and Defense to compare. So items should always display all 10 stats on the item comparison in the same consistent order. Basically items should roll with 10 stats, even if 6 of those stats are 0. Comparisons would be much easier and far more consistent.
Private matches should be available from the main menu like in DD1, hopefully, that's just a beta thing.
Sort order for your inventory doesn't save for very long, keeps going back to default.
Played one survival to wave 25 on medium, mana for upgrading everything took til like wave 20. That wasn't very much fun. Intended or going to release a genie pet?
I don't feel like the huntress gun is firing. Maybe it's just the weapons I got, but the feel of DPSing on the huntress is lackluster compared to the apprentice ranged fire right now, as far as the feedback loop goes.
I've seen it in other posts but I'll say it again, and it is probably just a rushed beta feature, but chat doesn't stay scrolled to the end of the conversation and there is no easy way to leave the chat unless you type something, because sometimes after hitting enter again it still wants you to type.
Not sure if this is just for beta, but there should be a loot filter or an automatic pick-up after each wave. Be nice not to see all those gray items on the ground after a while. A loot filter with advanced options would be even better. Like be able to set Legendary or 25 defensive power items with 3 tower stats and above. Bunch of checkboxes and sliders, you know the drill. lol.
The map overlay is hard to understand and not very helpful. K.I.S.S.
This may not be a right away thing, but an enemy speedup might be nice eventually. Waiting for 3000 enemies in survival takes a long time. Hopefully, that and survival saves can be implemented in the future.
Folders for inventory in dd1 were nice. Like to see that over DD2 stash tabs. Or something to better organize besides just filters.
Tooltips while hovering over the graphical settings on what they change would be helpful. Warframe does this nicely if I remember correctly.
Ever think of changing up the 4 base heroes. Maybe one of them is lost and needs to be rescued during a later point in the game. Just a thought.
A few nice things to say before I go.
I know it's the beta, but I installed this on my backup non ssd and the load times are basically non-existent, so try and keep that up for when the game begins to grow.
Holding ctrl to view the defense wheel is probably the best UI element in the game right now. Not sure how useful using the wheel will be once everybody learns their keybinds and what towers cost what, but that is a nice, simple, and informative circle. Only thing it doesn't have is your hero skills on it. So I still don't know what my second abilities do. But I like the wheel, an actual UI improvement over dd1 in my eyes.
I only had 1 ogre think about going back to the spawn and getting stuck, but he decided against it after realizing the floor was lava back there.
Keep on keeping on. Feedback is only given to promote growth. Nobody has known what to expect, so experiencing your vision for the first time is not going to be what they expected. In time hard work pays off, even when hard work was not expected. I'll leave you with my favorite quote that I think I made up or subconsciously stole from someone else. "The easiest way to exceed someone's expectations is to lower them first"